Exercise Trumps Gene In Teen Obesity : Shots - Health News Genes aren't destiny when it comes to gaining weight. Researchers have found that daily exercise helped teens overcome a particular genetic predisposition for obesity.
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Exercise Trumps Gene In Teen Obesity

Run for it. Photoillustration: NPR/iStockphoto.com hide caption

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Photoillustration: NPR/iStockphoto.com

Run for it.

Photoillustration: NPR/iStockphoto.com

Sure, genes may be a factor in some cases of obesity, but it just got a little harder to blame your parents. It turns out that one hour of moderate to vigorous exercise a day can help adolescents overcome a particular genetic predisposition to weight gain.

One of our pals at the Two-Way blog took a look at some new work on genes vs. exercise a few days ago, which got us wanting to know more.

European researchers looked at one gene in particular — it's called FTO rs9939609 polymorphism, or 'fatso' for short — in a population of 752 teenagers, and they found that physical activity can mitigate its effects. The study appears in the April edition of Archives of Pediatrics and Adolescent Medicine.

"In the study, the [FTO gene] was found to be associated with higher BMI and waist circumference in adolescents, but we saw a correlation between the gene and physical activity in each case," Dr. Jonatan Ruiz, lead researcher on the study, told Shots. In fact, the negative effects of the FTO gene "disappeared" for active adolescents, he said. Their body mass index scores and waist measurements were on par with those teenagers who don't carry the FTO gene.

The FTO gene has been shown in previous studies to predispose kids and adults to obesity. And a 2008 study showed that low physical activity accentuates the fat-gaining effects of that gene. But this is the first study to show that regular exercise can actually neutralize its effects — at least in adolescents.

"Because gene studies are so common now, people are a little bit alarmed that if you have a certain gene that predisposes you [to obesity] there's nothing you can do. But we showed that even if you have a gene that predisposes you to obesity, you can do something," Ruiz said. "Modify your lifestyle and your chances of modifying the negative effects of genetics can be very high."